yes u can swap the engine , but u should swap everything else too(tranny, rear diff, cooling system 0 it most likely will not be that easy but i could be wrong .
I used to have a 89 b2200 witha sbc it was nat to bad of a swap. you will have to weld in your own motor mounts. Use a chev tranny. shorty headers. I used the original rad, but moved it forward in the rad support a few inches so the motor would fit, the motor always stayed at 160